This invention relates to image intensifiers and more particularly to magnetic focused microchannel plate image intensifiers.
Like most television pickup tubes, the RCA Image Isocon can accept only a limited range of light levels in its optical image before an effect called "blooming" sets in. This effect if allowed to increase without limit, destroys the ability of the pickup tube to present an intelligible image to the viewer.
One requirement of users of television pickup systems is to have a television pickup system with day-night operational capabilities. Insertion of filters, lens aperturing and/or removal of the preamplifier image tube are permissible methods of accomplishing the day-night operational range capability. The conversion speed of mode change from day to night and night to day are drawbacks under the above possible methods, even under controlled conditions. For enemy countermeasure conditions, the interchange between day and night is far too slow to protect the television pickup system from destruction.